1. Field of Invention
This invention relates to lighting devices, specifically to hands-free devices used to illuminate a user's path.
2. Prior Art
Hikers, climbers, and trail-runners use artificial light to illuminate the trail at night. The introduction of the headlamp allowed hands-free operation of the lighting device, freeing their hands to operate other objects and devices, also minimizing the chance of dropping the lighting device.
However, headlamps have disadvantages. The light is located close to the user's eyes. The shadows cast by objects in the user's path are hidden by the objects themselves. This yields a lack of depth perception, making travel more difficult.
Another disadvantage of locating a light source on a user's head is apparent in cool weather. When a user exhales, the moisture from the user's breath is sharply illuminated. This momentarily blinds the user. This is also detrimental to the user's night-vision.
Headlamps are often bulky and cumbersome. Many people do not like objects on their heads. These users will avoid using headlamps.
These issues are not present with hand-held lights, however, these lights are not hands-free. A user is unable to use trekking poles or other items when using a hand-held light. Also, the natural motion of moving one's arms when walking or running must be stifled. A user is forced to hold the light, which can then be dropped. The user is also unable to put their hands in their pockets, thereby warming them.
One solution for this is a light with a clip. A light with a clip is hands-free, and does not have the same problems as a headlamp; however, its function is limited as well. A clip can be placed in many locations, but cannot be attached at the center of a backpack's hip-belt, as the buckle is there. If the buckle is placed off-center to accommodate a light clipped to the center of the belt, the buckle will be where padding usually is. This requires a hip-belt to have less padding, which decreases a user's comfort.
In addition, a light with a clip, a headlamp and a handheld light can be misplaced, and can be difficult to find when darkness is approaching. They can be buried deep in a pack, or worse, either forgotten at home, or lost on the trail.
Others have come to the conclusion of mounting a light on a user's waist. U.S. Pat. No. 4,849,863 (Gallegos, 1989), U.S. Pat. No. 5,045,979 (Stevens, 1991), U.S. Pat. No. 5,255,168 (Stevens, 1993), U.S. Pat. No. 5,359,501 (Stevens, 1994), and U.S. Pat. No. 6,056,412 (Atlee et al., 2000) all address this issue. All of these patents require a separate device from what a hiker would ordinarily carry, and are largely incompatible with a pack hip-belt. U.S. Pat. No. 4,283,756 (Beamon, 1981), attaches a light to a buckle, but the light flashes and is used solely for safety and not for illumination. It does not illuminate a user's path, and the batteries are in a separate housing, not even attached to the belt. U.S. Pat. No. 5,183,324 (Thomas, 1993) and U.S. Pat. No. 6,499,859 B2 (Petzl et al., 2002) describe a lamp with batteries built in, but it's a single housing, not a buckle of any kind. Finally, U.S. Pat. No. 6,979,098 B2 (Petzl et al., 2005) and U.S. patent application 2006/00561758 A1 (Petzl et al., filed Jan. 28, 2004) describe a swiveling optic system. These describe a binary system, it is either on or off; it is not used to direct a beam of light depending on the angle of the optics.